*E1 indicates the country in which the lamp has been tested and approved. Light sources approved in Germany display a "1".

*A capital "U" indicates a UV-reduced lamp in accordance with ECE requirements.- Such lamps are used, for example, in plastic headlights.

NOTE:Brand lamps fulfil these requirements.

*If DOT appears on a lamp, it means that the lamp is approved for the US market.- This identifier is required only for main headlight lamps – low and high beam.

*Finally, every lamp displays the approval mark of the relevant authority; in the case of E1, this is the Federal Motor Transport Authority in Flensburg. The approval mark consists of either 37R (E1) + a 5-digit number or just (E1) + a 3-digit number.- In most cases, lamps also display the manufacturer's own code to facilitate production batch tracking.